Driving means for continuous metal coating apparatus



Feb. 17, 1959 L. A. FUGASSI, JR 2,873,720

DRIVING MEANS FOR CONTINUOUS METAL COATING APPARATUS Filed D60. 1, 1954 INVENTOR z'enA.Fzz ass r.

M. E Q

' ATTORNEY Luc J BY United States atent DRIVING MEANS FGR CDNTINUOUS METAL COATING APPARATUS Lucien A. Fugassi, J12, Weirton, W. Va., assignor to National Steel Corporation, a corporation of Deiaware Application December 1, 1954, Serial No. 472,30

15 Claims. (Cl. 118-258) This invention relates to apparatus for continuous metal coating of strip material such as the coating of metal strip material with tin, zinc or aluminum, and more particularly to an arrangement for driving the coating rolls employed in such apparatus.

In apparatus for the continuous metal coating of strip material, such as the coating of steel strip with zinc in a hot dip galvanizing process, a tank is provided containing a bath of molten zinc and the strip material is passed through the molten zinc and then between coating or exit rolls which determine the thickness and character of the coating. The exit or coating rolls are partially submerged in the molten metal, up to the longitudinal axis of the rolls, for example, and are positively rotatably driven.

Since the coating rolls determine the thickness of the coated metal as well as the character of the coating, nonuniformities in the surface of the coating rolls require replacement of the rolls, otherwise a defective product continuous rotation in the molten metal to prevent damage to the surfaces of the coating roll by oxidation of the coating metal.

It is therefore an object of the present inventionto provide a novel driving arrangement for coating rolls of a continuous metal coating apparatus operable to allow the coating rolls to be moved upwardly above the bath of molten metal or laterally of the stationary strip of material while allowing their continuous rotation.

Another object is to provide a novel driving arrangement for coating rolls of a continuous metal coating apparatus characterized so that the coating rolls may be quickly removed from the apparatus and replaced with new coating rolls without requiring time-consuming and difiicult manipulations.

Still another object of the present invention is'to provide a novel driving spindle for use in rotatably connecting coating rolls of a continuous metal coating apparatus to a driving means including a coupling device allowing limited variations in the axial length of the spindle so that thev coating roll may be moved without breaking the driving connection. and Without terminating rotation of the rolls.

A still further object is to provide a novel driving spindle of the foregoing character in which the coupling device is operable for reducing the axial length of the driving spindle to allow the driving spindle to be dis- 7 'companying drawing which discloses one embodiment of ice the invention. It is to be expressly understood, however, that the drawing is designed for purposes of illustration only and not as a definition of the limits of the invention, reference for the latter purpose being had to the appended claims.

In the drawing, in which similar reference characters denote similar elements throughout the several views:

Fig. 1 is a view, partially in section, of a portion of a continuous metal coating apparatus diagrammatically illustrating a driving arrangement for the coating rolls constructed in accordance with the principles of the present invention;

Fig. 2 is a view in longitudinal section of a portion of the driving arrangement provided by the present invention;

' Fig. 3 is an elevational view in longitudinal section of another portion of the driving arrangement provided by the present invention; and

Fig. 4- is a horizontal sectional view of the structure shown in Fig. 3.

In apparatus for continuous metal coating of strip material of the type employing exit or coating rolls partially submerged in the molten metal, driving means for the coating rolls is' positioned adjacent the tank containing the molten metal opposite one end of the coating rolls and is necessarily mounted on a foundation at an elevation above the. top edges of the tank. According to the principles of the present invention, an elongated spindle or shaft is provided to form a direct connection between the driving means and one end of the coating rolls, a universal connection being provided between the ends of the spindle and the driving means and the coating rools. Due to the difference in elevation of the longitudinal axes of the coating roll and the driving means the elongated spindle is inclined downwardly toward the coating rolls, and in order to provide a compact arrangement the tank for the molten metal in the region beneath the elongated spindle is provided with an outwardly projecting trough extending along the spindle in a direction toward the driving means a sufiicient distance to prevent molten metal from flowing out of the tank. In order to allow the coating rolls to be moved upwardly away from the upper surface of the molten metal, or laterally away from the strip material, the elongated spindle is provided with means for allowing relative axial movement between its ends connected'to the coating rolls and the driving means while maintaining the driving connection. The elongated spindle also includes means operable for allowing extended axial movement of the elongated spindle relative to the driving means and away from the coating rolls so that the coating rollsvmay be removed from the apparatus upon a relatively simple operation which may be easily performed within a relatively short period of time.

With reference more particularly to Fig. l of the drawing, a coating roll driving arrangement embodying the principles of the present invention is disclosed in connection with a continuous metal coating apparatus for strip material including a tank 1'0 adapted to contain a bath of molten metal 11, the dotted line 12 indicating the upper surface of the molten metal. An exit or coating roll 13 is rotatably supported within the tank It) by means of a supporting member 14 rotatably receiving at its end a cylindrical bearing member 15 secured to the neck 16 of the roll. It is understood that both ends: of the roll are rotatably supported by asimilar arrangement of any suitable design which is only diagrammatically shown since it does not constitute a feature of the present invention. Also, a pair of rolls 13 are provided with their longitudinal axes parallel and generally lying in a horizontal plane with means for controlling the spacing therebetween to determine the thickness and character-of the coating on the strip matement.

rial fed therebetween. The supporting member 14 may in turn be supported by a suitable superstructure which may include means for elevating the coating rolls to a position above the surface 12of the molten metal, or the mounting for the coating rolls may be provided with means for moving the coating rolls away from each other laterally of the strip -material therebetween.

The driving means for the exit or coating rolls may comprise an electrically driven gear box 17 -mounted on a platform structure 19 and arranged to provide a pair of driving shafts, one for each of the coating rolls, although only one driving shaft 18 is shown in the drawing. The driving shaft 18 is spaced axially of one end of its respective coating roll 13 with its longitudinal axis lying in a plane above the longitudinal axis of the coating roll. The platform structure 19 may extend inwardly toward the coating roll to provide a continuous surface with its end adjacent the coating roll comprising a cantilever structure 20 which may constitute a support for superstructure 21 carrying the coating roll supporting members.

In accordance with the present invention, an elongated shaft or spindle 25 is provided for forming a connection between the driving shaft 18 and the coating roll 13. One end of the elongated shaft, which end is hereafter referred to as the outer end of the elongated shaft, is connected to the driving shaft 18 by means of a universal joint type of coupling device 26 which may be of any suitable conventional construction, while the other or inner end of the elongated shaft is pivotally joined to the adjacent end of the coating roll 13 in a novel manner described below. Inasmuch as the longitudinal axes of the driving shaft 18 and the coating roll 13 lie in vertically spaced planes with the coating roll axis being at a lower elevation, the longitudinal axis of the elongated shaft 25 is .inclined downwardly from the driving shaft as shown in the drawing. The elongated shaft passes through the platform structure 19 in the region of the cantilever structure 20 and the horizontal portion 27 and vertical portions 28 of the latter structure are provided with slotted openings 29 for the passage of the elongated shaft therethrough. For a purpose that will appear more fully below, the slotted openings 29 are properly dimensioned to allow vertical and/or lateral movement of the elongated shaft. Inasmuch as the coating roll 13 is positioned in the tank 10 partially submerged in the molten metal 11 with its longitudinal axis lying only slightly above the surface 12 of the molten metal, the tank 10 is provided with a trough-like member 30 projecting outwardly from the upper end of the tank beneath the elongated shaft and in a direction away from the coating roll and terminating at a point above the surface of the molten metal. The trough member 30 may be of generally Ushaped cross section, including side walls 31 and a bottom wall 32 inclined downwardly toward the tank. This arrangement allows a direct connection between-the driving means and the coating roll without requiring the ends of the coating roll to be spaced an abnormal distance from the wall of the tank and without requiring the use of a gear or other type of coupling means partially submerged within the molten metal.

As mentioned above, it is an object of the present invention to provide a novel driving arrangement between the driving shaft and the coating roll of a continuous metal coating apparatus including an elongated driving spindle designed in such a manner as to allow vertical or lateral movement of the coating roll without terminating the driving connection, and provided with means to allow the elongated spindle to be contracted axially in a direction away from the coating roll so that the coating roll may be removed from the apparatus without further manipulation ofthe driving arrange- The foregoing is accomplished by means of the '4 elongated spindle 25 including a novel coupling device 35. As shown in Fig. 2 of the drawing, the coupling device 35 includes an adjusting screw member 36 including an annular flange 37 projecting axially from one of its ends and adapted to extend inside one end of a tubular elongated shaft 38 which constitutes a major portion of the elongated driving spindle 25, the tubular shaft 38 being rigidly secured to the annular flange 37 by means of a plurality of quadraturely disposed rivets 39. The adjusting screw member 36 is provided with a longitudinal splined bore 40 adapted to slidably receive a splined end 41 of a shaft bearing member 42 which comprises another portion of the elongated driving spindle. The other end 43 of the shaft bearing member may be provided with splines for drivably engaging the coupling device 26 which may be of any conventional construction such as a ball bearing type. The coupling device 36 also includes a bushing member 44 comprising a cup-shaped portion 45 and a sleeve portion 46 joined together by means of bolts 47. The cup-shaped portion 45 defines a cylindrical chamber 48 through which the shaft bearing member 42 passes, the bottom wall 49 of the cup-shaped portion 44 being provided with an opening 50 housing an annular bushing member 51 for receiving the shaft bearing member. The sleeve portion 46- is provided with internal threads 52 for threadably cooperating with external threads 53 extending substantially throughout the length of the adjusting screw member 36. A lock nut 54 is also threadably' mounted on the adjusting screw member 36 for movement longitudinally of the latter member into and out of engagement with the end 55 of the sleeve portion 44. The adjusting screw member 36, the bushing member 44 and the lock nut 54 may be provided with hand operating members 56, 57 and 58, respectively, of the circular or wheel type. The shaft bearing mem ber 42 includes an annular flange member 60 projecting outwardly therefrom in the region of the shaft bearing member traversing the chamber 48. A pair of coil springs 61 and 62 are located within the chamber 48 on opposite sides of the flange member 60, the coil spring 61 is positioned between the flange member and the inside surface of the bottom wall 49 of the cupsbaped portion 45 while the coil spring 62 is positioned between the other side of the flange member 60 and an internal shoulder 63 of the sleeve portion 46. The annular flange 60 is provided on each of its sides and adjacent its outer periphery with annular bearings 64 and 65 for slidably engaging the respective ends of the coil springs 61 and 62.

The structure providing a universal connection between the inner end of the elongated driving spindle 25 and the coating roll 13 is illustrated in Figs. 3 and 4 of the drawing. As shown, the cylindrical bearing member 15 is provided with a longitudinal bore of the proper internal diameter to fit snugly over the cylindrical neck 16 of the coating roll, and the cylindrical bearing member is secured to the neck by means of a tapered pin 71 extending therethrough. The hollow cylindrical bearing member 15 extends outwardly beyond the end of the neck 16 and the cylindrical bore 70 of the extending portion receives a pair of spaced split sleeve sections 72 and 73. The sections 72 and 73 are preferably welded to the member 15 and are spaced apart so that their opposite edges define a pair of diametrically opposed longitudinal slots 74 and 75 extending parallel to the longitudinal axis of the coating roll. The inner end of the elongated shaft 25 terminates in a ball-shaped member 77 which may be internally formed with a supporting member 76 extending within the tubular shaft 38 to' which it is secured in any suitable manner. The ball-shaped member 77 is dimensioned to fit inside the split sleeves 72 and 73 and is provided with a transverse slot 78. The slot 78 is adapted to receive I 38 in a direction toward the coating roll.

required.

a connecting member 79 including diametric cylindrical pin portions 80 and 81 adapted to enter the slots 74 and '75, respectively. The forward end of the connect: ing member 79 projects outwardly beyond the front of the ball-shaped member 77 for contact with a spacer member 82 positioned in front of a bolt 83 threadably secured in the neck 16, the bolt 83 being provided with acentering recess for use in dressing the coating roll. As shown more clearly in Fig. 3 the inner end of the slot 78 is defined by a concave wall 84, and the inner side of the connecting member 79 contacts a point of the surface 84- for all angular positions of the shaft 38 with respect to the longitudinal axis of the coating roll.

In operation, assuming the elongated driving spindle is coupled between the driving shaft 18 and the coating roll 13 in the manner shown in the drawing, the coil spring 62 will urge the bushing member 44 and the adjusting screw member 36 and hence the tubular shaft This action urges the ball-shaped member 77 into the cylindrical opening defined by the split sleeve sections 72 and 73 of the connecting member 79 its pin portions 80 and l 81 lie in the slots 74 'and 75, respectively, and provide a driving connection between the driving spindle and the coating roll. When it is desired to elevate the coating roll to a position above the surface 12 of the molten 'metal or to move the supporting roll laterally from the strip material, as the case may be, the supporting member 14 is operated to effect the desired movement of the coating roll and the coupling device automatically functions to maintain the driving connection. Upon movement of the coating roll upwardly as shown in broken lines in Fig. 1, the distance between the coating roll and the driving shaft 18 decreases and axial contraction of the driving spindle occurs. The latter action takes place in the coupling device 35 wherein the adjust ing screw member 36 moves in a direction toward the driving shaft against the spring 62. In arrangements for moving the coating roll laterally away from the strip material axial extension of the driving spindle may be In such cases the adjusting screw member 36 moves in the opposite direction. In either case the characteristics of the spring 62 are such as to maintain the driving connection between the spindle and the coating roll. In both cases the spring 61 functions as a damping means.

member 79 and the spacer member 82 without disturbing the perpendicular relationship between the axes of the pin portions 80 and 81 and the longitudinal axis of the coating roll. The feature of maintaining the pin portions 80 and 81 in a plane perpendicular to the longitudina-l axis of the coating roll irrespective of changes in the angular position of the driving spindle provides a universal coupling arrangement in which the problem of coupling pin failure is overcome. b

When it becomes necessary to change a coating roll, the locking nut 54 is rotated away from the end 55 of the sleeve portion 46 in a direction toward the hand wheel 56 of the adjusting screw member 36. Then, by means of the hand wheel members 56 and 57 the adjusting screw member 36 and the bushing member 44 are relatively rotated in the opposite direction to move the screw member 36 into the sleeve portion 46 and thus reduce the length of the driving spindle 25 a sufiicient degree to move the ball-shaped member 77 outwardly beyond the free end of the cylindrical bearing member 15. The coating roll may then be removed without requiring further manipulation of the driving spindle. After a new coating roll is installed the driving connection is established by rotating the hand wheels 56 and 57 in the opposite direction to thread the screw member 36 out of the sleeve 46 while at the same time guiding the ball-shaped member 77 into the opening provided by the split sleeves 72 and 73. The length of the driving spindle is adjusted upon relative rotation of the hand wheels 56 and 57 and the device is then locked by rotating the locking bolt 54 into tightly threaded engagement with the end 55 of the sleeve 46. 7

There is thus provided by the present invention a novel arrangement including a driving spindle for forming a driving connection between a driving shaft and a coating roll of a continuous metal coating apparatus. The ar rangement is such that the coating roll may be moved upwardly and downwardly or laterally without interrupting rotation of the coating roll. Also, the arrangement is such that the driving spindle may be contracted axially and moved outwardly and out of contact with the coating roll to allow the coating roll to be removed and replaced within a minimum period of time and without requiring other manipulations of the driving arrangement. Moreover, the present invention provides a novel universal coupling of the pin and seat type which eliminates pin shearing failure.

Although one embodiment of the invention has been discussed and described herein, it is to be expressly understood that various changes and substitutions may be made therein without departing from the spirit of the invention, as well understood by those skilled in the art. Reference therefore will be had to the appended claims for a definition of the limits of the invention:

I claim:

1. In a continuous metal coating apparatus including a tank adapted for containing a bath of molten metal, a rotatable coating roll mounted in the tank and driving means disposed adjacent the tank opposite one end of the coating roll, an elongated spindle for forming a driving connection between the driving means and the coating roll, the spindle including a first portion and a second portion positioned in axial alignment with their adjacent ends connected by a coupling device, the unconnected ends of the first portion and the second portion adapted to be universally connected to the driving means and the coating roll, the coupling device including a first member connected to the adjacent end of the second portion and provided with a bore for slidably receiving the adjacent end of the first portion for relative axial movement between the first portion and the second portion, a second member supported by the first portion and adjustably secured to the first member for determining the length of the spindle between the unconnected ends of the first and second portions, and means for establishing a driving connection between the first portion and the first member.

2. A continuous metal coating apparatus as defined in claim 1 in which the coupling device includes means for limiting the relative axial movement between the first portion and the second portion.

3. A continuous metal coating apparatus as defined in claim 2 in which the coupling device includes resilient means for urging the second portion in a direction away from the adjacent end of the first portion.

4. In a continuous metal coating apparatus including a tank adapted for containing a bath of molten metal, a rotatable coating roll mounted in the tank and driving means disposed adjacent the tank opposite one end of the coating roll, an elongated spindle for forming a driving connection between the driving means for the coating roll, the spindle including a first portion and a second portion positioned in axial alignment with their adjacent ends connected by a coupling device, means for uni versally connecting the unconnected end of the first portion to the driving means, and means for universally connecting the unconnected end of the second portion to the one end of the coating roll, the coupling device including a first member connected to the adjacent end of the second portion and provided with a bore for slidably receiving the adjacent end of the first portion for relative axial movement between the first portion andthe second portion, a second member supported by the first portion and adjustably secured to the first member for determining the length of the spindle between the unconnected ends of the first and second portions, and means for establishing a driving connection between the first portion and the first member.

5. A continuous metal coating apparatus as defined in claim 4 in which the coupling device includes means for limiting the relative axial movement between the first portion and the second portion.

6. A continuous metal coating apparatus as defined in claim 5 in which the coupling device includes resilient means for urging the second portion in a direction away from the adjacent end of the first portion.

7. In a continuous metal coating apparatus including a tank adapted for containing a bath of molten metal, a rotatable coating roll mounted in the tank and driving means disposed adjacent the tank opposite one end of the coating roll, an elongated spindle for forming a driving connection between the driving means and the coating roll, the spindle including a first portion and a second portion positioned in axial alignment with their adjacent ends connected by a coupling device, means for universally connecting the other end of the first portion of the driving means, and means for universally connecting the other end of the second portion to the one end of the coating roll, the coupling device including a first member rigidly joined to the adjacent end of the second portion of the spindle, the first member being provided with a longitudinally extending external threaded surface and a longitudinal bore for slidably receiving the adjacent end of the first portion of the spindle for relative axial movement between the first portion and the second portion, a second member slidably mounted on the first portion of the spindle, means for limiting the relative longitudinal sliding movement between the second member and the first portion of the spindle, the second member being provided with a longitudinal bore having internal threads adapted to threadably receive the threaded surface of the first member, and a lock ring threadably mounted on the threaded surface of the first member adapted for movement into engagement with the second member.

8. A continuous metal coating apparatus as defined in claim 7 in which the second member provides a chamber surrounding the first portion of the spindle and in which the first portion includes a flange member extending outwardly into a chamber provided by the second member, the longitudinal dimension of the chamber being greater than the longitudinal dimension of the flange to determine the relative axial movement between the first portion and the second portion.

9. A continuous metal coating apparatus as defined in claim 8 including spring means positioned between the flange member and the chamber for urging the second portion in a direction away from the first portion.

10. In a continuous metal coating apparatus including a tank adapted for containing a bath of molten metal, a rotatable coating roll mounted in the tank and driving means disposed adjacent the tank opposite one end of the coating roll, an elongated spindle for forming a driving connection between the driving means and the coating roll, the spindle including a first portion and a second portion positioned in axial alignment with their adjacent ends connected by a coupling device, means for universally connecting the other end of the first portion to the driving means, and means for universally connecting the other end of the second portion to the one end of the coating roll, the coupling device including a first member rigidly joined to the adjacent end of the second portion of the spindle, the first member being provided with a longitudinally extending external threaded surface and a longitudinal bore for slidably receiving the adjacent end of the first portion of the spindle for relative axial movement between the first portion and the second portion, the longitudinal bore of the first member and the connected end of the first portion including cooperating longitudinal splines for forming a driving connection between the first member and the first portion, a cup-shaped member including a bottom portion provided with an opening for slidably receiving the first portion and side walls extending in a direction toward the first member and being provided with internal threads for threadably receiving'the external threads of the first member, the cup-shaped member providing an annular chamber surrounding an intermediate part of the first portion, the first portion including an annular flange extending outwardly from its intermediate portion into the chamber, the width of the flange being less than the longitudinal dimension of the chamber, and spring means positioned in the chamber on both sides of the flange.

11. In a continuous metal coating apparatus including a tank adapted for containing a bath of molten metal, a rotatable coating roll mounted in the tank, an elongated spindle for driving the roll and a detachable universal driving connection between one end of the spin dle and the roll, the universal driving connection including an axially extending tublular member secured to one end of the roll, means providing longitudinally extending slot means internally of the tubular member, a ballshaped member secured to the one end of the spindle, the ball-shaped member adapted to enter the tubular member and being provided with a transverse slot, and a connecting member lying in the transverse slot, the connecting member including cylindrical extensions projecting outwardly from opposite sides of the ball-shaped member for engagement with the slot means and a portion extending outwardly beyond the forward end of the ball-shaped member for engagement with the roll to space the ball-shaped member from the roll, the cylindrical extensions having a common axis perpendicular to the 1ongitudinal axis of the roll.

12. A continuous metal coating apparatus as defined in claim 7 in which the universal connection between the other end of the second portion and the one end of the roll includes an axially extending tubular member secured to the one end of the roll, means providing longitudinally extending slot means internally of the tubular member, a ball-shaped member secured to the one end of the spindle, the ball-shaped member adapted to enter the tubular member and being provided with a transverse slot, and a connecting member lying in the transverse slot, the connecting member including cylindrical extensions projecting outwardly from opposite sides of the ball-shaped member for engagement with the slot means and a portion extending outwardly beyond the forward end of the ball-shaped member for engagement with the roll to space the ball-shaped member from the roll, the cylindrical extensions having a common axis perpendicular to the longitudinal axis of the roll.

-13. In a continuous metal coating apparatus, a tank having side walls adapted for containing molten metal, a rotatable coating roll, means for mounting the roll in the tank with its lower portion submerged in the molten metal and with one of its ends closely adjacent one side wall of the tank, driving means located above the tank and adjacent the one side wall of the tank, a longitudinally expansible elongated spindle, means for universally connecting one end of the spindle to the driving means, means for universally connecting the other end of the spindle to the one end of the roll, and means providing a trough extending from the one side wall of the tank and communicating with the interior of the tank and extending upwardly and outwardly from the tank in a region beneath the spindle, the trough communicating with the tank at a level at least corresponding to the level of the molten metal and terminating at a level above the level of the molten metal.

14. In a continuous metal coating apparatus including a tank adapted for containing a bath of molten metal, a rotatable coating roll mounted in the tank and driving means disposed adjacent the tank opposite one end of the coating roll, an elongated spindle for forming a driving connection between the driving means and the coating roll, the spindle including first and second portions, means for universally connecting one end of the first portion to the driving means, means for universally connecting one end of the second portion to the coating roll, a coupling device for forming a driving connection between the other ends of the first and second portions, the coupling device including means for mounting the first and second portions for limited relative axial movement and means for urging the second portion in a direction toward the coating roll.

15. In a continuous metal coating apparatus including a tank adapted for containing a bath of molten metal, a rotatable coating roll mounted in the tank and driving means disposed adjacent the tank opposite one end of the coating roll, an elongated spindle for forming a driving connection between the driving means and the coating roll, the spindle including a first portion and a second portion positioned in axial alignment with their adjacent ends connected by a coupling device, the unconnected ends of the first portion and the second portion adapted to be universally connected to the driving means and the coating roll, the coupling device including a first member connected to the adjacent end of the second portion and provided with a bore for slidably receiving the adjacent end of the first portion for relative axial movement between the first portion and the second portion, a second member secured to the first member, means operating between the first portion and the second member for limiting relative axial movement between the first portion and the second portion, and means for establishing a driving connection between the first portion and the first member.

References Cited in the file of this patent UNITED STATES PATENTS 1,287,030 Jones Dec. 10, 1918 2,072,090 Anderson Mar. 2, 1937 2,660,979 Bills Dec. 1, 1953 

